Field of the Invention
This invention relates to a process of manufacturing a taper leaf spring by applying special rolls on a material plate for a taper leaf spring in order to form a taper toward a terminal of said material plate, and also relates to a device for this process.
According to a conventional process of manufacturing a taper leaf spring, the pressing extent of the rolling rollers is adjusted to get a desired taper considering the thickness of the material plate as basis, so that the taper portion of the plate spreads out at its both lateral sides to have a broader breadth. Therefore, it is further required to carry out such secondary work as cutting and abrading, grinding and abrading, etc. Hence, the work units are increased and the productivity is lowered. For preventing such defects, rolling means as shown in FIG. 1 (a) and (b) are usually employed.
At the rolling means illustrated in FIG. 1 (a), the upper roller is provided with flanges on its both edges so as to be of so-called grooved roller shape and the breadth regulating effect is thus expected.
At the rolling means illustrated in FIG. 1 (b), a rolling stand is used instead of the lower roller and this stand is provided with embankments on its both sides so that the breadth regulating effect is expected.
However, in either of the above two instances, the control of the breadth becomes uncertain when the shape of the flange or the embankment is lost by wear. Hence, problems exist as to the maintenance of precise dimension. Moreover, it is feared that the penetration of metallic scales between the flange portion and the lower roller or between the upper roller and the embankment of the rolling stand may take place to result in breakage or damage accidents.